* Update License header for all source files
- Add Apache 2.0 header to source files that did not have one.
- Update all existing headers dated to 2019 to be 2020
- Remove comma from License header to comply with the Apache 2.0
guidelines.
* Update Copyright notice
Use the standard Copyright notices outlined by the
[CNCF](https://github.com/cncf/foundation/blob/master/copyright-notices.md#copyright-notices)
* Propagate context changes in mix tests
We will need this for testing the correlation context and baggage
items propagation between the APIs.
* Add baggage interoperation tests
The test adds a baggage item to active OT span and some correlation
key value to current Otel span. Then makes sure that the OT span
contains both the baggage item and some translated version of the
correlation key value its Otel sibling got, and that the Otel span
contains both the correlation key value and the baggage item its OT
sibling got.
* Add hooks functionality to baggage propagation
This introduces two kinds of hooks into the correlation context
code.
The set hook gets called every time we set a Map in the context. The
hook receives a context with the Map and returns a new context.
The get hook gets called every time we get a Map from the context. The
hook receives the context and the map, and returns a new Map.
These hooks will be used for correlation context and baggage items
propagation between the Otel and OT APIs.
* Warn on foreign opentracing span
* fixup for using otel propagators
* Add utility function for setting up bridge and context
This prepares the context by installing the hooks, so the correlation
context and baggage items can be propagated between the APIs.
* Add bridge span constructor
So I do not need to remember about initializing a newly added member
in several places now.
* Propagate baggage across otel and OT APIs
This uses the set hook functionality to propagate correlation context
changes from Otel to OT spans by inserting keys and values into the
baggage items. The get hook functionality is used to propagate baggage
items from active OT span into the otel correlation context.
* Use correlation Map for baggage items
We will put this map into the context with correlation context
functions, and that is easier if we have correlation.Map, not
map[string]string.
* Use otel propagators in bridge
The otel propagators are now kinda sorta usable for opentracing
bridge. Some more work is needed to make it fully work, though -
correlation context set with the otel API is not propagated to OT
spans as baggage items yet.
Co-authored-by: Joshua MacDonald <jmacd@users.noreply.github.com>
* move bridge out of the experimental directory
* drop a leftover from experimental stuff in gitignore
found by accident when doing `git grep experimental`.
